[PATCH v2] mm: memory-failure: cleanup try_to_split_thp_page()

From: Kefeng Wang
Date: Tue Aug 09 2022 - 07:12:20 EST


Since commit 5d1fd5dc877b ("mm,hwpoison: introduce MF_MSG_UNSPLIT_THP"),
the action_result(,MF_MSG_UNSPLIT_THP,) called to show memory error event
in memory_failure(), so the pr_info() in try_to_split_thp_page() is only
needed in soft_offline_in_use_page().

Meanwhile this could also fix the unexpected prefix for "thp split failed"
due to commit 96f96763de26 ("mm: memory-failure: convert to pr_fmt()").

Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
v2: update changelog

mm/memory-failure.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 14439806b5ef..0dfed9d7b273 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1524,20 +1524,18 @@ static int identify_page_state(unsigned long pfn, struct page *p,
return page_action(ps, p, pfn);
}

-static int try_to_split_thp_page(struct page *page, const char *msg)
+static int try_to_split_thp_page(struct page *page)
{
+ int ret;
+
lock_page(page);
- if (unlikely(split_huge_page(page))) {
- unsigned long pfn = page_to_pfn(page);
+ ret = split_huge_page(page);
+ unlock_page(page);

- unlock_page(page);
- pr_info("%s: %#lx: thp split failed\n", msg, pfn);
+ if (unlikely(ret))
put_page(page);
- return -EBUSY;
- }
- unlock_page(page);

- return 0;
+ return ret;
}

static void unmap_and_kill(struct list_head *to_kill, unsigned long pfn,
@@ -2079,7 +2077,7 @@ int memory_failure(unsigned long pfn, int flags)
* page is a valid handlable page.
*/
SetPageHasHWPoisoned(hpage);
- if (try_to_split_thp_page(p, "Memory Failure") < 0) {
+ if (try_to_split_thp_page(p) < 0) {
action_result(pfn, MF_MSG_UNSPLIT_THP, MF_IGNORED);
res = -EBUSY;
goto unlock_mutex;
@@ -2505,8 +2503,11 @@ static int soft_offline_in_use_page(struct page *page)
struct page *hpage = compound_head(page);

if (!PageHuge(page) && PageTransHuge(hpage))
- if (try_to_split_thp_page(page, "soft offline") < 0)
+ if (try_to_split_thp_page(page) < 0) {
+ pr_info("soft offline: %#lx: thp split failed\n",
+ page_to_pfn(page));
return -EBUSY;
+ }
return __soft_offline_page(page);
}

--
2.35.3